Source code for uds.can.flow_control

"""
Implementation specific for Flow Control CAN packets.

This module contains implementation of :ref:`Flow Control CAN packet <knowledge-base-can-flow-control>` attributes:
 - :ref:`Flow Status <knowledge-base-can-flow-status>`
 - :ref:`Block Size <knowledge-base-can-block-size>`
 - :ref:`Separation Time minimum (STmin) <knowledge-base-can-st-min>`
"""

__all__ = ["CanFlowStatus", "CanSTminTranslator", "CanFlowControlHandler", "UnrecognizedSTminWarning",
           "AbstractFlowControlParametersGenerator", "DefaultFlowControlParametersGenerator",
           "FlowControlParametersAlias"]

from abc import ABC, abstractmethod
from copy import deepcopy
from typing import Optional, Tuple
from warnings import warn

from aenum import unique

from uds.utilities import (
    InconsistentArgumentsError,
    NibbleEnum,
    RawBytesAlias,
    RawBytesListAlias,
    TimeMillisecondsAlias,
    ValidatedEnum,
    validate_nibble,
    validate_raw_byte,
    validate_raw_bytes,
)

from .addressing_format import CanAddressingFormat
from .addressing_information import CanAddressingInformation
from .frame_fields import DEFAULT_FILLER_BYTE, CanDlcHandler


[docs] class UnrecognizedSTminWarning(Warning): """ Warning about STmin value that is reserved and therefore not implemented. .. note:: If you have a documentation that defines a meaning of :ref:`STmin <knowledge-base-can-st-min>` value for which this warning was raised, please create a request in `issues management system <https://github.com/mdabrowski1990/uds/issues/new/choose>`_ and provide this documentation for us. """
[docs] @unique class CanFlowStatus(ValidatedEnum, NibbleEnum): """ Definition of Flow Status values. :ref:`Flow Status (FS) <knowledge-base-can-flow-status>` is a 4-bit value that enables controlling Consecutive Frames transmission. """ ContinueToSend: "CanFlowStatus" = 0x0 # type: ignore """Asks to resume Consecutive Frames transmission.""" Wait: "CanFlowStatus" = 0x1 # type: ignore # noqa: F841 """Asks to pause Consecutive Frames transmission.""" Overflow: "CanFlowStatus" = 0x2 # type: ignore # noqa: F841 """Asks to abort transmission of a diagnostic message."""
[docs] class CanSTminTranslator: """ Helper class that provides STmin values mapping. :ref:`Separation Time minimum (STmin) <knowledge-base-can-st-min>` informs about minimum time gap between a transmission of two following Consecutive Frames. """ MAX_STMIN_TIME: TimeMillisecondsAlias = 127 """Maximal time value (in milliseconds) of STmin.""" MIN_VALUE_MS_RANGE: int = 0 """Minimal value of STmin in milliseconds range (raw value and time value in milliseconds are equal).""" MAX_VALUE_MS_RANGE: int = 127 """Maximal value of STmin in milliseconds range (raw value and time value in milliseconds are equal).""" MIN_RAW_VALUE_100US_RANGE: int = 0xF1 """Minimal raw value of STmin in 100 microseconds range.""" MAX_RAW_VALUE_100US_RANGE: int = 0xF9 """Maximal raw value of STmin in 100 microseconds range.""" MIN_TIME_VALUE_100US_RANGE: TimeMillisecondsAlias = 0.1 """Minimal time value (in milliseconds) of STmin in 100 microseconds range.""" MAX_TIME_VALUE_100US_RANGE: TimeMillisecondsAlias = 0.9 """Maximal time value (in milliseconds) of STmin in 100 microseconds range.""" __FLOATING_POINT_ACCURACY: int = 10 """Accuracy used for floating point values (rounding is necessary due to float operation in python)."""
[docs] @classmethod def decode(cls, raw_value: int) -> TimeMillisecondsAlias: """ Map raw value of STmin into time value. .. note:: According to ISO 15765-2, if a raw value of STmin that is not recognized by its recipient, then the longest STmin time value (0x7F = 127 ms) shall be used instead. :param raw_value: Raw value of STmin. :return: STmin time in milliseconds. """ validate_raw_byte(raw_value) if cls.MIN_VALUE_MS_RANGE <= raw_value <= cls.MAX_VALUE_MS_RANGE: return raw_value if cls.MIN_RAW_VALUE_100US_RANGE <= raw_value <= cls.MAX_RAW_VALUE_100US_RANGE: return (raw_value - 0xF0) * 0.1 warn(message=f"STmin 0x{raw_value:X} is not recognized by this version of the package.", category=UnrecognizedSTminWarning) return cls.MAX_STMIN_TIME
[docs] @classmethod def encode(cls, time_value: TimeMillisecondsAlias) -> int: """ Map time value of STmin into raw value. :param time_value: STmin time in milliseconds. :raise TypeError: Provided value is not int or flow type. :raise ValueError: Value out of supported range. :return: Raw value of STmin. """ if not isinstance(time_value, (int, float)): raise TypeError(f"Provided value is not int or float type. Actual type: {type(time_value)}") if cls._is_ms_value(time_value): return int(time_value) if cls._is_100us_value(time_value): return int(round(time_value * 10, 0) + 0xF0) raise ValueError(f"Provided value is out of valid STmin ranges. Actual value: {time_value}")
[docs] @classmethod def is_time_value(cls, value: TimeMillisecondsAlias) -> bool: """ Check if provided value is a valid time value of STmin. :param value: Value to check. :return: True if provided value is a valid time value of STmin, False otherwise. """ if not isinstance(value, (int, float)): return False return cls._is_ms_value(value) or cls._is_100us_value(value)
[docs] @classmethod def _is_ms_value(cls, value: TimeMillisecondsAlias) -> bool: """ Check if provided argument is STmin time value in milliseconds. :param value: Value to check. :return: True if provided valid value of STmin time in milliseconds, False otherwise. """ if not cls.MIN_VALUE_MS_RANGE <= value <= cls.MAX_VALUE_MS_RANGE: return False return value % 1 == 0
[docs] @classmethod def _is_100us_value(cls, value: TimeMillisecondsAlias) -> bool: """ Check if provided argument is STmin time value in 100 microseconds. :param value: Value to check. :return: True if provided valid value of STmin time in 100 microseconds, False otherwise. """ if not cls.MIN_TIME_VALUE_100US_RANGE <= value <= cls.MAX_TIME_VALUE_100US_RANGE: return False return round(value % 0.1, cls.__FLOATING_POINT_ACCURACY) in (0, 0.1)
[docs] class CanFlowControlHandler: """Helper class that provides utilities for Flow Control CAN Packets.""" FLOW_CONTROL_N_PCI: int = 0x3 """N_PCI value of Flow Control.""" FS_BYTES_USED: int = 3 """Number of CAN Frame data bytes used to carry CAN Packet Type, Flow Status, Block Size and STmin.""" BS_BYTE_POSITION: int = 1 """Position of a data byte with :ref:`Block Size <knowledge-base-can-block-size>` parameter.""" STMIN_BYTE_POSITION: int = 2 """Position of a data byte with :ref:`STmin <knowledge-base-can-st-min>` parameter."""
[docs] @classmethod def create_valid_frame_data(cls, *, addressing_format: CanAddressingFormat, flow_status: CanFlowStatus, block_size: Optional[int] = None, st_min: Optional[int] = None, dlc: Optional[int] = None, filler_byte: int = DEFAULT_FILLER_BYTE, target_address: Optional[int] = None, address_extension: Optional[int] = None) -> RawBytesListAlias: """ Create a data field of a CAN frame that carries a valid Flow Control packet. .. note:: This method can only be used to create a valid (compatible with ISO 15765 - Diagnostic on CAN) output. Use :meth:`~uds.can.flow_control.FlowControlHandler.create_any_frame_data` to create data bytes for a Flow Control with any (also incompatible with ISO 15765) parameters values. :param addressing_format: CAN addressing format used by a considered Flow Control. :param flow_status: Value of Flow Status parameter. :param block_size: Value of Block Size parameter. This parameter is only required with ContinueToSend Flow Status, leave None otherwise. :param st_min: Value of Separation Time minimum (STmin) parameter. This parameter is only required with ContinueToSend Flow Status, leave None otherwise. :param dlc: DLC value of a CAN frame that carries a considered CAN Packet. - None - use CAN Data Frame Optimization (CAN ID value will be automatically determined) - int type value - DLC value to set. CAN Data Padding will be used to fill the unused data bytes. :param filler_byte: Filler Byte value to use for CAN Frame Data Padding. :param target_address: Target Address value carried by this CAN Packet. The value must only be provided if `addressing_format` uses Target Address parameter. :param address_extension: Address Extension value carried by this CAN packet. The value must only be provided if `addressing_format` uses Address Extension parameter. :raise InconsistentArgumentsError: Invalid DLC value was provided. :return: Raw bytes of CAN frame data for the provided Flow Control packet information. """ validate_raw_byte(filler_byte) ai_data_bytes = CanAddressingInformation.encode_ai_data_bytes(addressing_format=addressing_format, target_address=target_address, address_extension=address_extension) frame_dlc = cls.get_min_dlc(addressing_format) if dlc is None else dlc frame_data_bytes_number = CanDlcHandler.decode_dlc(frame_dlc) fs_data_bytes = cls.__encode_valid_flow_status(flow_status=flow_status, block_size=block_size, st_min=st_min, filler_byte=filler_byte) fc_bytes = ai_data_bytes + fs_data_bytes if len(fc_bytes) > frame_data_bytes_number: raise InconsistentArgumentsError("Provided value of `dlc` is too small.") data_bytes_to_pad = frame_data_bytes_number - len(fc_bytes) if data_bytes_to_pad > 0: if dlc is not None and dlc < CanDlcHandler.MIN_BASE_UDS_DLC: raise InconsistentArgumentsError(f"CAN Frame Data Padding shall not be used for CAN frames with " f"DLC < {CanDlcHandler.MIN_BASE_UDS_DLC}. Actual value: dlc={dlc}") return fc_bytes + data_bytes_to_pad * [filler_byte] return fc_bytes
[docs] @classmethod def create_any_frame_data(cls, *, addressing_format: CanAddressingFormat, flow_status: CanFlowStatus, dlc: int, block_size: Optional[int] = None, st_min: Optional[int] = None, filler_byte: int = DEFAULT_FILLER_BYTE, target_address: Optional[int] = None, address_extension: Optional[int] = None) -> RawBytesListAlias: """ Create a data field of a CAN frame that carries a Flow Control packet. .. note:: You can use this method to create Flow Control data bytes with any (also inconsistent with ISO 15765) parameters values. It is recommended to use :meth:`~uds.can.flow_control.FlowControlHandler.create_valid_frame_data` to create data bytes for a Flow Control with valid (compatible with ISO 15765) parameters values. :param addressing_format: CAN addressing format used by a considered Flow Control. :param flow_status: Value of Flow Status parameter. :param st_min: Value of Separation Time minimum (STmin) parameter. Leave None to not insert this parameter in a Flow Control data bytes. :param block_size: Value of Block Size parameter. Leave None to not insert this parameter in a Flow Control data bytes. :param dlc: DLC value of a CAN frame that carries a considered CAN Packet. :param filler_byte: Filler Byte value to use for CAN Frame Data Padding. :param target_address: Target Address value carried by this CAN Packet. The value must only be provided if `addressing_format` uses Target Address parameter. :param address_extension: Address Extension value carried by this CAN packet. The value must only be provided if `addressing_format` uses Address Extension parameter. :raise InconsistentArgumentsError: DLC value is too small. :return: Raw bytes of CAN frame data for the provided Flow Control packet information. """ validate_raw_byte(filler_byte) ai_data_bytes = CanAddressingInformation.encode_ai_data_bytes(addressing_format=addressing_format, target_address=target_address, address_extension=address_extension) frame_data_bytes_number = CanDlcHandler.decode_dlc(dlc) fs_data_bytes = cls.__encode_any_flow_status(flow_status=flow_status, block_size=block_size, st_min=st_min) fc_bytes = ai_data_bytes + fs_data_bytes if len(fc_bytes) > frame_data_bytes_number: raise InconsistentArgumentsError("Provided value of `dlc` is too small.") data_bytes_to_pad = frame_data_bytes_number - len(fc_bytes) if data_bytes_to_pad > 0: return fc_bytes + data_bytes_to_pad * [filler_byte] return fc_bytes
[docs] @classmethod def is_flow_control(cls, addressing_format: CanAddressingFormat, raw_frame_data: RawBytesAlias) -> bool: """ Check if provided data bytes encodes a Flow Control packet. .. warning:: The method does not validate the content of the provided frame data bytes. Only, :ref:`CAN Packet Type (N_PCI) <knowledge-base-can-n-pci>` parameter is checked whether contain Flow Control N_PCI value. :param addressing_format: CAN Addressing Format used. :param raw_frame_data: Raw data bytes of a CAN frame to check. :return: True if provided data bytes carries Flow Control, False otherwise. """ ai_bytes_number = CanAddressingInformation.get_ai_data_bytes_number(addressing_format) return raw_frame_data[ai_bytes_number] >> 4 == cls.FLOW_CONTROL_N_PCI
[docs] @classmethod def decode_flow_status(cls, addressing_format: CanAddressingFormat, raw_frame_data: RawBytesAlias) -> CanFlowStatus: """ Extract Flow Status value from Flow Control data bytes. .. warning:: The method does not validate the content of the provided frame data bytes. There is no guarantee of the proper output when frame data in invalid format (incompatible with ISO 15765) is provided. :param addressing_format: CAN Addressing Format used. :param raw_frame_data: Raw data bytes of a considered CAN frame. :raise ValueError: Provided frame data of a CAN frames does not carry a Flow Control CAN packet. :return: Flow Status value carried by a considered Flow Control. """ if not cls.is_flow_control(addressing_format=addressing_format, raw_frame_data=raw_frame_data): raise ValueError(f"Provided `raw_frame_data` value does not carry a Flow Control packet. " f"Actual values: addressing_format={addressing_format}, raw_frame_data={raw_frame_data}") ai_bytes_number = CanAddressingInformation.get_ai_data_bytes_number(addressing_format) return CanFlowStatus(raw_frame_data[ai_bytes_number] & 0xF)
[docs] @classmethod def decode_block_size(cls, addressing_format: CanAddressingFormat, raw_frame_data: RawBytesAlias) -> int: """ Extract Block Size value from Flow Control data bytes. .. warning:: The method does not validate the content of the provided frame data bytes. There is no guarantee of the proper output when frame data in invalid format (incompatible with ISO 15765) is provided. :param addressing_format: CAN Addressing Format used. :param raw_frame_data: Raw data bytes of a considered CAN frame. :raise ValueError: Provided frame data of a CAN frames does not carry a Flow Control CAN packet with Continue To Send Flow Status. :return: Block Size value carried by a considered Flow Control. """ flow_status = cls.decode_flow_status(addressing_format=addressing_format, raw_frame_data=raw_frame_data) if flow_status != CanFlowStatus.ContinueToSend: raise ValueError(f"Provided `raw_frame_data` value does not carry a Flow Control packet with " f"ContinueToSend Flow Status. Actual values: addressing_format={addressing_format}, " f"raw_frame_data={raw_frame_data}, flow_status={flow_status}") ai_data_bytes_number = CanAddressingInformation.get_ai_data_bytes_number(addressing_format) return raw_frame_data[ai_data_bytes_number + cls.BS_BYTE_POSITION]
[docs] @classmethod def decode_st_min(cls, addressing_format: CanAddressingFormat, raw_frame_data: RawBytesAlias) -> int: """ Extract STmin value from Flow Control data bytes. .. warning:: The method does not validate the content of the provided frame data bytes. There is no guarantee of the proper output when frame data in invalid format (incompatible with ISO 15765) is provided. :param addressing_format: CAN Addressing Format used. :param raw_frame_data: Raw data bytes of a considered CAN frame. :raise ValueError: Provided frame data of a CAN frames does not carry a Flow Control CAN packet with Continue To Send Flow Status. :return: Separation Time minimum (STmin) value carried by a considered Flow Control. """ flow_status = cls.decode_flow_status(addressing_format=addressing_format, raw_frame_data=raw_frame_data) if flow_status != CanFlowStatus.ContinueToSend: raise ValueError(f"Provided `raw_frame_data` value does not carry a Flow Control packet with " f"ContinueToSend Flow Status. Actual values: addressing_format={addressing_format}, " f"raw_frame_data={raw_frame_data}, flow_status={flow_status}") ai_data_bytes_number = CanAddressingInformation.get_ai_data_bytes_number(addressing_format) return raw_frame_data[ai_data_bytes_number + cls.STMIN_BYTE_POSITION]
[docs] @classmethod def get_min_dlc(cls, addressing_format: CanAddressingFormat) -> int: """ Get the minimum value of a CAN frame DLC to carry a Flow Control packet. :param addressing_format: CAN addressing format that considered CAN packet uses. :return: The lowest value of DLC that enables to fit in provided Flow Control packet data. """ ai_data_bytes_number = CanAddressingInformation.get_ai_data_bytes_number(addressing_format) return CanDlcHandler.get_min_dlc(ai_data_bytes_number + cls.FS_BYTES_USED)
[docs] @classmethod def validate_frame_data(cls, addressing_format: CanAddressingFormat, raw_frame_data: RawBytesAlias) -> None: """ Validate whether data field of a CAN Packet carries a properly encoded Flow Control. :param addressing_format: CAN Addressing Format used. :param raw_frame_data: Raw data bytes of a CAN frame to validate. :raise ValueError: Provided frame data of a CAN frames does not carry a properly encoded Flow Control CAN packet. """ validate_raw_bytes(raw_frame_data) cls.decode_flow_status(addressing_format=addressing_format, raw_frame_data=raw_frame_data) min_dlc = cls.get_min_dlc(addressing_format=addressing_format) dlc = CanDlcHandler.encode_dlc(len(raw_frame_data)) if min_dlc > dlc: raise ValueError("Provided `raw_frame_data` is too short.") if dlc < CanDlcHandler.MIN_BASE_UDS_DLC and dlc != min_dlc: raise ValueError("Provided `raw_frame_data` has improper length (incorrect Data Length Optimization).")
@classmethod def __encode_valid_flow_status(cls, flow_status: CanFlowStatus, block_size: Optional[int] = None, st_min: Optional[int] = None, filler_byte: int = DEFAULT_FILLER_BYTE) -> RawBytesListAlias: """ Create Flow Control data bytes with CAN Packet Type and Flow Status, Block Size and STmin parameters. .. note:: This method can only be used to create a valid (compatible with ISO 15765 - Diagnostic on CAN) output. :param flow_status: Value of Flow Status parameter. :param block_size: Value of Block Size parameter. This parameter is only required with ContinueToSend Flow Status, leave None otherwise. :param st_min: Value of Separation Time minimum (STmin) parameter. This parameter is only required with ContinueToSend Flow Status, leave None otherwise. :param filler_byte: Filler Byte value to use for CAN Frame Data Padding. :return: Flow Control data bytes with CAN Packet Type and Flow Status, Block Size and STmin parameters. """ CanFlowStatus.validate_member(flow_status) if flow_status == CanFlowStatus.ContinueToSend: validate_raw_byte(block_size) # type: ignore validate_raw_byte(st_min) # type: ignore else: if block_size is not None: validate_raw_byte(block_size) if st_min is not None: validate_raw_byte(st_min) return [(cls.FLOW_CONTROL_N_PCI << 4) ^ flow_status, block_size if block_size is not None else filler_byte, st_min if st_min is not None else filler_byte] @classmethod def __encode_any_flow_status(cls, flow_status: int, block_size: Optional[int] = None, st_min: Optional[int] = None) -> RawBytesListAlias: """ Create Flow Control data bytes with CAN Packet Type and Flow Status, Block Size and STmin parameters. .. note:: This method can be used to create any (also incompatible with ISO 15765 - Diagnostic on CAN) output. :param flow_status: Value of Flow Status parameter. :param block_size: Value of Block Size parameter. Leave None to skip the Block Size byte in the output. :param st_min: Value of Separation Time minimum (STmin) parameter. Leave None to skip the STmin byte in the output. :return: Flow Control data bytes with CAN Packet Type and Flow Status, Block Size and STmin parameters. Some of the parameters might be missing if certain arguments were provided. """ validate_nibble(flow_status) output = [(cls.FLOW_CONTROL_N_PCI << 4) ^ flow_status] if block_size is not None: validate_raw_byte(block_size) output.append(block_size) if st_min is not None: validate_raw_byte(st_min) output.append(st_min) return output
FlowControlParametersAlias = Tuple[CanFlowStatus, Optional[int], Optional[int]] """Alias of :ref:`Flow Control <knowledge-base-can-flow-control>` parameters which contains: - :ref:`Flow Status <knowledge-base-can-flow-status>` - :ref:`Block Size <knowledge-base-can-block-size>` - :ref:`Separation Time minimum <knowledge-base-can-st-min>`"""
[docs] class AbstractFlowControlParametersGenerator(ABC): """Definition of Flow Control parameters generator."""
[docs] def __iter__(self) -> "AbstractFlowControlParametersGenerator": """Get iterator object - called on each First Frame reception.""" return self
[docs] @abstractmethod def __next__(self) -> FlowControlParametersAlias: """ Generate next set of Flow Control parameters - called on each Flow Control message building. :return: Tuple with values of Flow Control parameters (Flow Status, Block Size, ST min). """
[docs] class DefaultFlowControlParametersGenerator(AbstractFlowControlParametersGenerator): """ Default (recommended to use) Flow Control parameters generator. Every generated Flow Control parameters will contain the same (valid) values. """ def __init__(self, block_size: int = 0, st_min: int = 0, wait_count: int = 0, repeat_wait: bool = False) -> None: """ Set values of Block Size and Separation Time minimum parameters to use. :param block_size: Value of :ref:`Block Size <knowledge-base-can-block-size>` parameter to use. :param st_min: Value of :ref:`Separation Time minimum <knowledge-base-can-st-min>` parameter to use. :param wait_count: Number of Flow Control packets to send with :ref:`Flow Status <knowledge-base-can-flow-status>` equal 1 (wait). :param repeat_wait: How to send Flow Control packets with WAIT Flow Status: - True - send them before every Flow Control packet with Flow Status=0 (continue to send) - False - send them only once before the first Flow Control packet with Flow Status=0 (continue to send) """ self.block_size = block_size self.st_min = st_min self.wait_count = wait_count self.repeat_wait = repeat_wait self._remaining_wait: Optional[int] = None
[docs] def __iter__(self) -> "DefaultFlowControlParametersGenerator": """Get iterator object.""" iterator = deepcopy(self) if iterator.wait_count > 0: iterator._remaining_wait = iterator.wait_count else: iterator._remaining_wait = None return iterator
[docs] def __next__(self) -> FlowControlParametersAlias: """ Generate next set of Flow Control parameters. :return: Tuple with values of Flow Control parameters: - :ref:`Flow Status <knowledge-base-can-flow-status>` - :ref:`Block Size <knowledge-base-can-block-size>` - :ref:`Separation Time minimum <knowledge-base-can-st-min>` """ if self._remaining_wait is None: return CanFlowStatus.ContinueToSend, self.block_size, self.st_min if self._remaining_wait == 0: if self.repeat_wait: self._remaining_wait = self.wait_count return CanFlowStatus.ContinueToSend, self.block_size, self.st_min self._remaining_wait -= 1 return CanFlowStatus.Wait, None, None
@property def block_size(self) -> int: """Value of :ref:`Block Size <knowledge-base-can-block-size>` parameter.""" return self.__block_size @block_size.setter def block_size(self, value: int): """ Set value of :ref:`Block Size <knowledge-base-can-block-size>` parameter. :param value: Value to set. """ validate_raw_byte(value) self.__block_size = value @property def st_min(self) -> int: """Value of :ref:`Separation Time minimum <knowledge-base-can-st-min>` parameter.""" return self.__st_min @st_min.setter def st_min(self, value: int): """ Set value of :ref:`Separation Time minimum <knowledge-base-can-st-min>` parameter. :param value: Value to set. """ validate_raw_byte(value) self.__st_min = value @property def wait_count(self) -> int: """Get number of Flow Control packets to send with WAIT :ref:`Flow Status <knowledge-base-can-flow-status>`.""" return self.__wait_count @wait_count.setter def wait_count(self, value: int): """ Set number of Flow Control packets to send with WAIT :ref:`Flow Status <knowledge-base-can-flow-status>`. :param value: Value to set. """ if not isinstance(value, int): raise TypeError("Provided value is not int type.") if value < 0: raise ValueError("Provided value is les than 0.") self.__wait_count = value @property def repeat_wait(self) -> bool: """ Flag informing how to send Flow Control packets with WAIT Flow Status. - True - send them before every Flow Control packet with Flow Status=0 (continue to send) - False - send them only once before the first Flow Control packet with Flow Status=0 (continue to send) """ return self.__repeat_wait @repeat_wait.setter def repeat_wait(self, value: bool): """ Set flag informing how to send Flow Control packets with WAIT Flow Status. - True - send them before every Flow Control packet with Flow Status=0 (continue to send) - False - send them only once before the first Flow Control packet with Flow Status=0 (continue to send) """ self.__repeat_wait = bool(value)